In a lithographic printing press printing ink is transferred from an ink fountain or the like by a series of ink distribution rollers to the printing plate. Similarly, water or other dampening fluid is transferred from a pan or a sump by a series of dampening rollers to the printing plate. The particular dampening roller which actually applies the water or other fluid to the printing plate is known as the dampening form roller.
A common problem associated with lithographic printing presses is the problem of "railroad tracking". This problem occurs when the dampening form roller picks up ink from the printing plate, particularly when dry spots occur on the dampening form roller. Such dry spots are particularly susceptible to picking up printing ink. During the rotation of the dampening form roller, ink may be deposited on certain non-ink receptive areas of the plate cylinder, which results in ink streaks appearing on the final print product. Water streaks may also appear on the printing plate, which necessitates the use of alcohol and alcohol-substitutes in the dampening fluid to break up the surface tension of the water and reduce streaking.